Process for the production of an antislip rubber material



1 rubber which' is 'provided with 'insertions Patented Aug. 13, 1935 PRooE'ss' FOR v toAzo Alrtienges No Drawingfi PATENT THE PRODUCTION OF-AN' I j NT, R ER ATQBE 1 :Josef Otto Liichinger, Biel; Switzerland,-.assignor iiiLUNITE'D TATES ells chaft Biel, Switzerland, n

Application March-a1; 1922,

,In Germany February 12, 1932 serial 'ijolaims. (o1.1qt- 23 '-'The present invention relates to anti-slip'-rubber for. covering wheels and-the like vents, with absolute'certainty, ding on slippery which prvehicles from k m surfaces. I

It has already been proposed, in thejpr'oduction of such covers, to embed hard' vulcanizing the caoutchouc mass, have, however, as'fa rule, not fulfilled. the desired purpose, and have, moreover, resulted in too rapid wearing of the'material. 7

--'Iheins'er'tions, consisting of hard substances,-

The presentinvention relates to an anti-slip of hard substances and which does not show the aforementioned disadvantages, but on the contrary,

body of the rubber tires is with The arrangement of the solid m'te proportions with the caoutchouc with the I aid of a carrier which fixes the granular material in position after incorporation with the caoutchouc, so that any movement within the caoutchouc after vulcanization of the rubber is desiredefiect'i i of grain of the hard m'ain'a fine state rendered impossible. Three conditionsare'n'eces sary for obtaining the (2) Adefinite percentage addition ortheagram' ular material incorporated the-"rubber; which must not be deviated from in 'eitherdire tion; c: V I :v I A 3 The use'of a carrienwhich keeps the i terial-in position" after embedding With regard-to the first condition'u'th hard material, such' quartz," emery, -"corundum and the like, must not exceed about .1' .mm. ini size of Y grain. i

of. division? With regard to the second conditionythefinely.

grained material must be incorporated-withthe caoutchouc in an amount T varying between '10 and 30 per cent; *If more tlia'n'the amountlindi ca'ted is employed; the' -final' product?will'be brit tle, if less, the anti-slip properties of the finished material will be decreased.

With regard to the third condition the carrier or fixing material consisting of a suitable agent, which is adapted to fix the hard material,

or rubber mass, is applied to the granulated material and dried on the same so that the finely or the like is coated with to a certain extent, glazed,

grained quartz mass a binding agent and,

tion in the caoutchouc of the dried material, which is still in a finely grained form even after being coated with the binding agent.

If the hard material so prepared is uniformly distributed in the caoutchouc mass to be vulcanized in the size of grain and the quantitative proportions indicated, and if the rubber is thereafter finished in the usual manner, theglazing on the granular insertions softens owing to the heat generated by the treatment and becomes again capable of binding. In this! way it firmly fixes the insertions in position. A material actually results which is highly elastic but still highly resistant, in which it is impossible for the insertion to wander into the body of the rubber tire and consequently have a disturbing eiTect thereon, but in which the embedded grains, owing to the pressure of the moving wheels, are gradually pushedoutwards. The running surface is theresothat there is nothing to prevent fine distribu by roughened and absolute security against skidding afforded. further promoted running surfaces.

The process for the production of' anti-skid This process is, of course, still by the gradual wear of the 25 for example quartz or the like in the caoutchouc rubber according to this invention ay be carv migration of the particles into the body of the ried out as follows: tire.

-yieldable, vulcanized 'uted particles of the particles to Example Quartz of about 1 mm. size ofgrain is cleansed by elutriation and coated with a viscous binding agent which may, for example consist of 150 parts by weight of litharge, and 50 parts by weight-of glycerine. g

The coating is effected by stirring the quartz into the binding agent. It-is dried at a moderate temperature. The resulting finely grained mass I covered with a glazing of binding agent is thoroughly sieved and the material-thereafter incorporated in the usual masticators, rollers or the like, with"- the caoutchouc in a proportion of about,20 per cent by,

weight, if. desired agents, and finely distributed therein, the mixture is worked up in the usual manner into a moulded article.

WhatIclaimis: i i

1. A tire tread composition formed of resilient rubber containing distrib-i ofthe particlesinto the body of the tire.

"! yieldable vulcanized rubber containing 10 to 30% v '3. A tire tread composition formed of resilient,

of distributed-particles 01 hard material selected from'the group cons corundum and coated with litharge and glycerine which bonds them to the rubber to prevent manner by ,means 7 after which I treads and abrasive material coated with ting of quartz, emery and v 4. A tire tread composition'formed of vulcanized rubber composition containing to 30% of distributed particles of hard material selected from the group consisting of quartz, emery, and corundum and coated with a material consisting of three parts litharge and one part glycerine, the particles being bonded to the-rubber by said coating material.

1 5. A process for making yieldable, rubber composition for use as tire 10 a non-skid resilient,

treads and the like, which comprises applying a coating of litharge and glycerine'to thegrains ofsuitablahard, granular material, distributing said granular material in unvulcanized caoutchouc, adding a suitable vulcanizing agent to the mixture andsubjecting the whole to a vulcanizing process. I

'6. A process for making a non-skid resilient, yieldable, rubber composition: for, use .as tire a coating of litharge, and glycerine to grains of at least one member of the groupconsistingotv quartz, emery and corundum, distributing said granular material in unvulcanized .caoutchouc, adding a suitable vulcanizing agent to the mix ture and subjecting the whole to a vulcanizin process. 1 7. Arprocess for making a nonf-skidresilient,

JOSEF o'rro LiiCHINGER.

the like, which comprises applying a suitable vul- 30. yieldable, rubber compositionfor; use as the V i which comprisesfapplyinz 

